Corrugated paperboard containers and packaging materials have been used for some time to box all kinds of products for shipment. In some of these corrugated paperboard containers, corner posts are utilized to firmly position an item within the container and maintain it in a spaced relationship from the sidewall of the container such that a foreign object would have to enter a substantial distance into the container before contacting the item to thereby damage it in some way. Corner posts are generally comprised of four folded up pieces of corrugated paperboard which are inserted in the corners of the shipping container and friction fit between the product and the container sidewall. This packaging technique is especially useful in boxing consumer goods such as dishwashers and the like where a painted surface must be protected from damage to preserve the appearance of the item. Furthermore, these corner posts serve to fix the item in position with a minimal amount of contact against the item's surface. With this minimal contact, damage to the item's surface through rubbing or shifting of the item during shipment is minimized. Still another advantage of corner posts is that when they are sized to extend the full height of the container, they can significantly add to the compressive strength of the container to thereby permit more containers to be stacked atop each other during storage and shipment.
Because of the many advantages of corner posts, and their relatively inexpensive nature, corner post packaging made from corrugated paperboard has proliferated in application. However, one of the few drawbacks with a corner post packaging arrangement is the labor intensive nature of the prior art designs. Typical prior art designs for a corner post comprise a flat sheet of corrugated paperboard which has a number of regular score lines or slit score lines to divide the sheet into a series of panels. For ease in shipment and handling, the corner posts are manufactured in a flat configuration. For usage, it is then necessary for a shipping clerk to grasp the corner post "flat", bend the corner post about its score lines to roll it up into shape, and hold the corner post in its operable configuration as it is inserted between the container sidewall and the item being boxed therein. As the "flats" are rolled up into the corner post configuration, some attention and effort must be given to holding the corner post in its proper configuration or the corner post has a distinct tendency to unroll. Typically, with prior art corner post designs, there is no structure provided in the corner post to help hold it in its operable configuration and instead the shipping clerk is relied on to grapple with the corner post, container, and product as the corner post is inserted into the shipping container. Furthermore, as there is no structure to aid the shipping clerk in holding the corner post in its operable configuration, corner post designs are typically very simplistic with generally only two panels of the corner post overlapping. Of course, this minimizes the amount of corrugated that can be utilized in the corner post which minimizes the amount of compressive strength that the corner post can add to the shipping container. For corner posts having a more complex or intricate design, generally greater labor and attention need be devoted to utilize these designs in packaging. Therefore, a greater expense is experienced through additional labor costs in completing the packaging of any one item.
To solve these and other problems of the prior art, the inventors herein have succeeded in developing a corner post which may be simply and cheaply manufactured, but which provides a somewhat greater compressive strength due to the increased amount of corrugated panels utilized in the design and which also provides decreased time to convert the corner post from its flat orientation to its operable configuration. Furthermore, the corner post has two panels which are pre-glued to help the shipping clerk both in reconfiguring the corner post from its flat to its operable orientation and also to help the shipping clerk maintain the corner post in its operable configuration as it is inserted within the container itself. Thus, a great savings in labor is experienced with the corner post of the present invention over that of the prior art, while providing greater compressive strength than was previously attainable.
In essence, the corner post design of the present invention is comprised of a single sheet of corrugated which is folded over into two portions, both portions being substantially the same width. A series of score lines or slit scores are utilized to divide the corner post into a series of panels, much as in the prior art designs. However, significantly, the two end or outermost panels of the upper and lower portions are joined together across their face, such as by gluing or the like. Thus, the corner post is fixed in a folded over orientation, at least in its flat configuration. To reconfigure the corner post from its flat orientation (as utilized for shipping and handling in bulk) to its operable configuration, a shipping clerk need only apply pressure at the edges of the corner post flat which causes the upper and lower portions to separate and then to collapse inwardly as the necessary right angle is formed between the two largest panels. The inner panels then self-align virtually automatically due to the arrangement of the score lines. The corner post has a greater tendency to remain in the operable configuration than the roll-up design of the prior art and, certainly, there is no tendency for the corner post to unroll as the end panels have been permanently glued together. It should be noted that although this process has been described by a number of distinct steps, in a typical conversion from the flat configuration to the operable configuration, a shipping clerk soon becomes skilled in "snapping" these corner posts into shape such that it is virtually a one-step, instantaneous process which rather markedly reduces the amount of time required for the shipping clerk to ready a corner post for insertion into the shipping container. This results in a significant labor savings, and hence decreased cost to package an item for shipment.
Although some of the principal advantages and features of the present invention have been described above, a greater understanding of the invention may be attained by referring to the drawings and description of the preferred embodiment which follows.